New research by scientists at Osaka International University and Kobe University in Japan has revealed that women need to work harder to start sweating during exercise.

The report - published in Experimental Physiology - said that untrained females required a higher body temperature than other groups to start sweating. According to study co-ordinator Yoshimitsu Inoue, women could be at a "disadvantage" in warmer conditions if they are required to sweat a lot during exercise.

The research also found that the differences between men and women were greater as intensity levels increase. However, the reason may be evolutionary, according to Inoue. "The lower sweat loss in women may be an adaptation strategy that attaches importance to survival in a hot environment, while the higher sweat rate in men may be a strategy for greater efficiency of action or labour," he said.

"Both men and women can acclimate themselves better to heat if they exercise regularly before a heat wave comes."